Coir wick log and method

ABSTRACT

A biodegradable log includes a strip of absorbent material embedded therein and at least one wick extending from the strip outside of the log. The wick draws moisture into the biodegradable log in order to maintain an aqueous environment for embedded vegetation. Holes may be provided at least partially through the log diameter and along the log length to facilitate log placement and installation.

CROSS-REFERENCES TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Serial No. 60/469,402, filed May 12, 2003, the entire content of which is herein incorporated by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

[0002] (NOT APPLICABLE)

BACKGROUND OF THE INVENTION

[0003] Water causes sedimentation and erosion by displacing particles within water beds and shore lines. Attempts to halt sedimentation and erosion have thus far utilized construction materials to form pilings, retaining walls and sheet pilings. Such construction elements, however, used alone are neither in harmony with nature nor long-lived. More recently, some efforts have been made to utilize seeds for stabilizing embankments along dams and shore lines, however germination could only occur during certain seasons of the year and only under the most favorable conditions. Such seeds rarely germinated in sufficient numbers to provide reliable vegetative growth.

[0004] A number of companies build and sell logs made from coir, held in shape by heavyweight coir roping. A coir material can be formed into a porous fabric-like material that is biodegradable. The biodegradable logs can then be stacked at the toe of slopes in or out of streams to provide a stabilizing edge for the slopes. This edge allows plants to grow, eventually rooting into the log.

[0005] Plants are often planted within the log to promote this process. After the plants root into the log and sloped bank, the root systems become the stabilizing method, and the log naturally biodegrades away.

[0006] A problem with this approach, however, is that coir logs tend to lose moisture faster than soils. This loss of moisture dries the roots of the plants in or adjacent the log, slowing the natural rooting process. This is particularly true for plants that are installed in the log. These plants are isolated from the natural soils of the bank and tend to dry (much like a flower in a pot).

[0007] Another problem with existing products resides in the difficulty of positioning and installing stakes. The stakes are difficult to drive through the coir material, oftentimes requiring the use of additional stakes to hold the log in place while the primary stakes are driven through the log, which adds time and therefore cost to the installation process.

BRIEF SUMMARY OF THE INVENTION

[0008] It would thus be desirable to incorporate a system in such coir logs that would better deliver moisture to plants in or adjacent the log. It would additionally be desirable to reduce installation time by reducing the difficulty in positioning and installing stakes. The invention encompasses a biodegradable log incorporating an assembly of materials to create a wicking effect to draw moisture from the stream into the log. An absorbent material is embedded in the log, and one or more wicks extend outside of the log. The wicks draw moisture to the inner areas of the log, thereby providing moisture for the plants. The invention also encompasses a biodegradable log including stake holes at least partially through the log diameter and spaced along the log length to facilitate placement and installation of the stakes.

[0009] In an exemplary embodiment of the invention, a biodegradable log having a longitudinal axis includes a strip of absorbent material embedded therein substantially parallel to the longitudinal axis. At least one wick extends from the strip outside of the log. With a plurality of wicks, the wicks are spaced apart, preferably equally spaced, along the longitudinal axis.

[0010] The wicks may extend at least four inches outside of the log, and preferably extend about twelve inches outside of the log. In one arrangement, the log is generally cylindrical including an outer circumference, and the strip is embedded in the log at a location spaced from the outer circumference. Assuming the log includes a diameter D, the location is spaced from the outer circumference by at least 0.1*D. In one preferred arrangement, the location is spaced about four inches from the outer circumference.

[0011] The log is preferably formed of a coir material, and strip is preferably formed of cotton rope. In one arrangement, the strip and the wick are formed of the same material, such as cotton rope.

[0012] In another exemplary embodiment of the invention, a method of constructing a biodegradable log for stabilizing stream slopes includes the steps of embedding a strip of absorbent material along a longitudinal axis of the biodegradable log; and extending at least one wick from the strip outside of the log.

[0013] In still another exemplary embodiment of the invention, a method of stabilizing a stream slope includes the steps of placing the biodegradable log of the invention along the stream slope and extending the wick into the stream; and planting at least one plant within the log adjacent the strip. The placing step may be performed by staking the biodegradable log along the stream slope.

[0014] In yet another exemplary embodiment of the invention, a biodegradable log is formed of a coir material and has a longitudinal axis. The log includes a strip of absorbent material embedded within the log and disposed spaced from an exterior surface of the log and substantially parallel to the longitudinal axis. A plurality of wicks extend from the strip outside of the log. The wicks are configured to draw moisture from outside of the log toward the strip.

[0015] In another exemplary embodiment, a biodegradable log includes a plurality of holes extending at least partially through a diameter of the log and spaced along the longitudinal axis. Preferably, the holes are spaced about 2-3 feet apart and extend completely through the diameter of the log.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] These and other aspects and advantages of the present invention will be described in detail with reference to the accompanying drawings, in which:

[0017]FIG. 1 is a side view of the wick log according to the present invention;

[0018]FIG. 2 is an end view of the wick log illustrated in FIG. 1; and

[0019]FIG. 3 is a side view of a biodegradable log incorporating stake holes.

DETAILED DESCRIPTION OF THE INVENTION

[0020] The use of biodegradable logs in sediment control has been known. Such logs are typically formed using a coir material held in shape by a heavyweight coir roping or netting material or the like. An example of such a coir log is disclosed in U.S. Pat. No. 5,678,954, the disclosure of which is hereby incorporated by reference. Since such a biodegradable log is known, the details in the manner of assembling the log and the materials therein will not be further described. Although coir material is preferred according to the present invention, other biodegradable materials that may be constructed into a porous log or other suitable shape may also be used.

[0021] With reference to FIGS. 1 and 2, the biodegradable log 10 of the present invention is generally formed in a cylindrical shape including a longitudinal axis 12. A strip of absorbent material 14 such as cotton rope or the like is embedded within the log 10 substantially parallel to the longitudinal axis 12. At least one wick 16 extends from the strip of material 14 outside of the log 10. Preferably, as shown, a plurality of wicks 16 are spaced along the longitudinal axis 12. In one embodiment, the plurality of wicks 16 are equally spaced along the longitudinal axis 12, such as about two feet apart (depending on a length of the log 10).

[0022] In manufacturing the biodegradable log 10, the coir material is piled into a heavyweight coir roping, which defines the resulting shape of the log 10. The material strip 14 and one or more wicks 16 can be appropriately set during the coir piling/filling process such that the material 14 and wicks 16 are suitably embedded within the log 10, with the wicks 16 extending outside of the log.

[0023] As shown, the material strip 14 is embedded in the log 10 at a location spaced from an outer circumference of the log. Preferably, the material strip 14 is spaced at least a distance corresponding to 10% of the log diameter (0.1*D). In an exemplary arrangement, the material strip 14 is spaced about four inches from the outer circumference.

[0024] In use, the log 10 is placed or staked along a stream slope or the like with the one or more wicks 16 extending into the stream. Suitable vegetation is planted within the log 10 adjacent the material strip 14. The wicks 16 draw moisture from the stream to the material strip 14 and maintain an aqueous environment for the embedded vegetation. Over time, the vegetation roots into the log 10 and the stream slope so that the root systems serve to stabilize the stream slope, and the log naturally biodegrades away.

[0025] In order to accommodate raising and lowering stream levels, it is preferable to extend the wicks 16 at least four inches outside of the log and more preferably about twelve inches or more outside of the log. The wick material may vary, including cotton-based materials, jute-based materials, or other suitable water absorbent natural materials. Preferably, both the material strip 14 and the wicks 16 are formed of the cotton rope material.

[0026] With reference to FIG. 3, in order to facilitate placement and installation of stakes for securing the log, a plurality of holes 20 are fabricated into the log 10 at least partially through the log diameter, preferably completely through, and spaced along the log length, preferably about two to three feet apart. With the log 10 in place, one or more stakes 22 can be easily inserted through the log 10 and into the ground G to secure the log 10. The plurality of holes 20 provides the installer the ability to select a best location for staking, e.g., depending on the ground beneath.

[0027] The holes 20 are formed during the fiber piling or weaving process using cylindrical mandrels. When the log shape is formed, the mandrels are removed, leaving the holes therein. Preferably, the mandrels are comprised of a cardboard sleeve, although certainly other materials may be used as would be apparent to those of ordinary skill in the art, and the invention is not meant to be limited to cardboard.

[0028] With the construction of the present invention, since conventional coir logs tend to lose moisture faster than soils, the added material strip and wicks enable the log to maintain an aqueous environment to promote growth and rooting of embedded vegetation. The construction is inexpensive to manufacture, and installation is practically as simple as installation of conventional coir log products.

[0029] While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention is not to be limited to the disclosed embodiments, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. 

1. A biodegradable log having a longitudinal axis, the log comprising a strip of absorbent material embedded therein substantially parallel to the longitudinal axis and at least one wick extending from the strip outside of the log.
 2. A biodegradable log according to claim 1, comprising a plurality of wicks extending from the strip outside of the log, wherein the plurality of wicks are spaced apart along the longitudinal axis.
 3. A biodegradable log according to claim 2, wherein the plurality of wicks are equally spaced along the longitudinal axis.
 4. A biodegradable log according to claim. 3, wherein the wicks are spaced about two feet apart along the longitudinal axis.
 5. A biodegradable log according to claim 3, wherein the wicks extend at least four inches outside of the log.
 6. A biodegradable log according to claim 3, wherein the wicks extend about twelve inches outside of the log.
 7. A biodegradable log according to claim 1, wherein the wick extends at least four inches outside of the log.
 8. A biodegradable log according to claim 1, wherein the wick extends about twelve inches outside of the log.
 9. A biodegradable log according to claim 1, wherein the log is generally cylindrical including an outer circumference, and wherein the strip is embedded in the log at a location spaced from the outer circumference.
 10. A biodegradable log according to claim 9, wherein the log includes a diameter D, and wherein the location is spaced from the outer circumference by at least 0.1*D.
 11. A biodegradable log according to claim 9, wherein the location is spaced about four inches from the outer circumference.
 12. A biodegradable log according to claim 1, wherein the log is formed of a coir material.
 13. A biodegradable log according to claim 1, wherein the strip is formed of cotton rope.
 14. A biodegradable log according to claim 1, wherein the strip and the wick are formed of the same material.
 15. A biodegradable log according to claim 1, wherein the strip and the wick are formed of cotton rope.
 16. A biodegradable log according to claim 1, further comprising a plurality of holes extending at least partially through a diameter of the log and spaced along the longitudinal axis.
 17. A method of constructing a biodegradable log for stabilizing stream slopes, the method comprising: embedding a strip of absorbent material along a longitudinal axis of the biodegradable log; and extending at least one wick from the strip outside of the log.
 18. A method of stabilizing a stream slope, the method comprising: placing the biodegradable log of claim 1 along the stream slope and extending the wick into the stream; and planting at least one plant within the log adjacent the strip.
 19. A method according to claim 18, comprising planting a plurality of plants within the log adjacent the strip.
 20. A method according to claim 18, wherein the placing step comprising staking the biodegradable log along the stream slope.
 21. A biodegradable log formed of a coir material and having a longitudinal axis, the log comprising: a strip of absorbent material embedded within the log and disposed spaced from an exterior surface of the log and substantially parallel to the longitudinal axis; and a plurality of wicks extending from the strip outside of the log, the wicks configured to draw moisture from outside of the log toward the strip.
 22. A biodegradable log having a longitudinal axis, the log comprising a strip of absorbent material embedded therein substantially parallel to the longitudinal axis and means for drawing moisture from outside of the log toward the strip.
 23. A biodegradable log having a longitudinal axis, the log comprising a plurality of holes extending at least partially through a diameter of the log and spaced along the longitudinal axis.
 24. A biodegradable log according to claim 23, wherein the holes are spaced about 2-3 feet apart.
 25. A biodegradable log according to claim 23, wherein the holes extend completely through the diameter of the log. 